Search found 6605 matches

by hoglet
Fri Nov 24, 2017 8:33 pm
Forum: hardware
Topic: Open Source Logic Analyzer Experiments
Replies: 97
Views: 3559

Re: Open Source Logic Analyzer Experiments

Another option would be to change the fx2 to do synchronised sampling by feeding phi clock into the fx2. This also reduces the amount of captured data. Yes, this would definitely help, assuming it can sample on the falling edge. But I'm guessing we would have to write custom firmware for the FX2 to...
by hoglet
Fri Nov 24, 2017 8:24 pm
Forum: hardware
Topic: Open Source Logic Analyzer Experiments
Replies: 97
Views: 3559

Re: Open Source Logic Analyzer Experiments

I've been doing some quite extensive testing over the last few days, running the Dormann and Bruce Clark test suites. This is helped iron out a few bugs in the decoder. This has involved some long captures of up to 60s of bus data (which seems to be the max the FX2 board can do), which results in a ...
by hoglet
Fri Nov 24, 2017 7:29 pm
Forum: acorn atom
Topic: Atom scrambled screen
Replies: 8
Views: 233

Re: Atom scrambled screen

Have you tried pressing BREAK? If that makes no difference, most likely something is stopping the 6502 from running properly. You will get the same symptoms if the 6502 is removed completely. Usually it's a RAM fault, as the 2114L RAM chips are notoriously unreliable. Probably IC51/IC52. Can you pos...
by hoglet
Fri Nov 24, 2017 11:09 am
Forum: hardware
Topic: Open Source Logic Analyzer Experiments
Replies: 97
Views: 3559

Re: Open Source Logic Analyzer Experiments

before I order, is this the right board https://www.amazon.co.uk/EZ-USB-FX2LP-CY7C68013A-Analyzer-Development/dp/B008B48VDA It may work, but you might have some additional fiddling to do. It is a different board to the one I have. I would recommend buying the one from Hobby Components, as they have...
by hoglet
Thu Nov 23, 2017 8:17 am
Forum: hardware
Topic: Open Source Logic Analyzer Experiments
Replies: 97
Views: 3559

Re: Open Source Logic Analyzer Experiments

Dave, is this still the correct pinout -- D0-7 to PB0-7, RnW to PD0, 2MHzE to PD3, and /RST to PD6? ... A bunch more signals are available on the Electron, so I figure I may as well wire as many as I can to PD*. READY, /IRQ, and /NMI are obvious ones to do. Otherwise it's just address lines, which ...
by hoglet
Wed Nov 22, 2017 8:00 am
Forum: acorn atom
Topic: I've got an Acorn Atom... Woot Woot :) (changed title (again) :)
Replies: 23
Views: 744

Re: At the risk of sounding pathetic...I want an Acorn Atom... :)

now for the unappreciative part: ( I suspect a lot of work went into the Core for the Acorn Atom.... but i was wondering.... how difficult it would be to use the 36 expansion pins on the zx-uno to support a matrix keyboard: as laid out by the original Acorn schematic.... 10 x 6 matrix with 3 additi...
by hoglet
Mon Nov 20, 2017 10:23 pm
Forum: hardware
Topic: ZX81 emulator
Replies: 48
Views: 1369

Re: ZX81 emulator

Fantastic!

Which Co Pro does it run on?
by hoglet
Mon Nov 20, 2017 10:04 pm
Forum: hardware
Topic: Open Source Logic Analyzer Experiments
Replies: 97
Views: 3559

Re: Open Source Logic Analyzer Experiments

fordp wrote:I wonder if a Raspberry Pi cobbler would work to connect the tube to the Logic analyser?

I think possibly not, because it looks like some of the power pins (e.g. the two +5V pins) are connected together.

Do you have one?
by hoglet
Mon Nov 20, 2017 2:31 pm
Forum: upcoming and recent events & exhibitions
Topic: ABUG EAST MIDLANDS (Winter Warmer) 17-19 November 2017 (Leicestershire) BOOKING THREAD
Replies: 139
Views: 5472

Re: ABUG EAST MIDLANDS (Winter Warmer) 17-19 November 2017 (Leicestershire) BOOKING THREAD

There is already an FPGA BBC Micro - if the FPGA "bods" extended this to be an FPGA BBC Master there could exist, in theory, a completely "solid-state FPGA/new hardware based" Domesday system. FYI, Beeb FPGA already has a Master mode: http://www.stardot.org.uk/forums/viewtopic.p...
by hoglet
Mon Nov 20, 2017 12:03 pm
Forum: hardware
Topic: Open Source Logic Analyzer Experiments
Replies: 97
Views: 3559

Re: Open Source Logic Analyzer Experiments

Part 6 has been posted here

In summary, we can now debug by connecting the Logic Analyzer only to the Tube connector:
IMG_1136.JPG

This is using the cheap (£13.44 delivered) logic analyzer, from here.

Dave
by hoglet
Sun Nov 19, 2017 1:04 pm
Forum: acorn atom
Topic: ICE T65/Z80/6809
Replies: 615
Views: 30537

Re: ICE T65/Z80/6809

flynnjs wrote:Er.... maybe I'll just cut and strap my mini board to be the same as the ones everyone else has... ?

Great idea :D
by hoglet
Sun Nov 19, 2017 12:45 pm
Forum: acorn atom
Topic: ICE T65/Z80/6809
Replies: 615
Views: 30537

Re: ICE T65/Z80/6809

I note the latest MCS file for the LX9 mini board supports the UART on pins 51/55 where my board has it on 46/47. So I have a booting board but no UART right now :-) I'm not sure how best to deal with this, and I guess you are the only person with an original board.... I'd rather not create a whole...
by hoglet
Sun Nov 19, 2017 11:56 am
Forum: hardware
Topic: read / write to JIM
Replies: 36
Views: 970

Re: read / write to JIM

Pernod wrote: 3000 when 0xFCFF & 0xF = ?

It's actually 0xFCFF & 0xF0 = 0x50

(i.e. testing bits 7..4)

See this thread:
http://www.stardot.org.uk/forums/viewto ... 08#p183808

Dave
by hoglet
Sun Nov 19, 2017 11:21 am
Forum: acorn atom
Topic: ICE T65/Z80/6809
Replies: 615
Views: 30537

Re: ICE T65/Z80/6809

Bingo! Getting it to sample data on Phi0_a has fixed the problem it's now accessing memory correctly, and boots, running the RAM test passes too now which is good. Excellent!! Next up I want to implement a a command on the AVR section that will "free run" but log so run as fast as it can ...
by hoglet
Sat Nov 18, 2017 6:47 pm
Forum: acorn atom
Topic: ICE T65/Z80/6809
Replies: 615
Views: 30537

Re: ICE T65/Z80/6809

Oddly I know filling with a value seems to successfully write the value, if I do a fill of the screen RAM the display clears to the used character, reading them back however results in random data. Though it seems slightly better now :) it is still corrupting For example scrolling the screen result...
by hoglet
Sat Nov 18, 2017 4:12 pm
Forum: acorn atom
Topic: ICE T65/Z80/6809
Replies: 615
Views: 30537

Re: ICE T65/Z80/6809

I suspect it may be a slight timing issue as for some things the Apple seems to use an externally generated phi1 rather tha the one generated by the CPU. That's the only slightly unusual thing I can spot as well, and it's used in the RAM control signals. There is lots of scope for tweaking the inte...
by hoglet
Sat Nov 18, 2017 3:49 pm
Forum: acorn atom
Topic: Atom on FPGA based retro-computers
Replies: 10
Views: 1926

Re: Atom on FPGA based retro-computers

waltermixxx wrote:Thanks Hoglet for the fpga core.

You are most welcome!
by hoglet
Sat Nov 18, 2017 1:08 pm
Forum: acorn atom
Topic: ICE T65/Z80/6809
Replies: 615
Views: 30537

Re: ICE T65/Z80/6809

Can you point me at a schematic for your Apple II?
by hoglet
Fri Nov 17, 2017 10:01 am
Forum: acorn atom
Topic: ICE T65/Z80/6809
Replies: 615
Views: 30537

Re: ICE T65/Z80/6809

Prime wrote:Has someone made the level converter boards or are a schematic / board layout available that I could use?

Jason Flynn has, and if you ask quickly he might be able to bring one to ABUG.
http://www.xeropage.co.uk/shop/index.ph ... er=product

Dave
by hoglet
Thu Nov 16, 2017 10:15 pm
Forum: hardware
Topic: New 65C02/W65C816 copro
Replies: 72
Views: 3967

Re: New 65C02/W65C816 copro

Does hoglet's OSWORD test help at all? http://stardot.org.uk/forums/viewtopic.php?p=106198#p106198 http://stardot.org.uk/forums/viewtopic.php?p=106346#p106346 I downloaded the ZIP and opened the file in a text editor. It looks like a BASIC program so I fired up BeebEm and imported it to a new SSD i...
by hoglet
Wed Nov 15, 2017 10:12 am
Forum: hardware
Topic: MMFS Development and Support
Replies: 693
Views: 33726

Re: MMFS Development and Support

Sorry, should have mentioned that in my initial post. I'm running the model B, sideways ram version V1.36 Hmm, I've tried and haven't been able to replicate this. Which probably just means there is some small but significant difference between your setup and mine. Could you possibly post a screen s...
by hoglet
Tue Nov 14, 2017 10:08 pm
Forum: hardware
Topic: MMFS Development and Support
Replies: 693
Views: 33726

Re: MMFS Development and Support

I'm running SWMMFS in one of my SWRAM banks and generally it works very well. However, I've noticed that immediately after a BREAK, the *FREE command doesn't work. If I do a *CAT first, it then works. Is this a problem with my setup, or can others replicate this? What version are you running? I'll ...
by hoglet
Tue Nov 14, 2017 10:07 pm
Forum: acorn atom
Topic: CMT Rom Board
Replies: 2
Views: 140

Re: CMT Rom Board

The manual and schematic are posted here:
http://www.stardot.org.uk/forums/viewto ... 44&t=13337

Try ?#A000=N where N is 1..4 to select ROM 1..4

Dave
by hoglet
Mon Nov 13, 2017 10:54 pm
Forum: hardware
Topic: EEPROM - the Holy Grail of Sideways Rom?
Replies: 346
Views: 27607

Re: EEPROM - the Holy Grail of Sideways Rom?

Are your 28C256s from a reputable source? There are lots of fakes on ebay.

Dave
by hoglet
Mon Nov 13, 2017 8:31 pm
Forum: other vintage computer hardware, software and games
Topic: Apple II problem.....
Replies: 6
Views: 254

Re: Apple II problem.....

Doh! That's caught be out a couple of times as well.

It should be only the STA that is doing the dummy read (unless you are crossing a page boundary, which I don't think you are).

Dave
by hoglet
Mon Nov 13, 2017 8:25 pm
Forum: emulators
Topic: MAME: Tube devices
Replies: 68
Views: 3010

Re: MAME: Tube devices

I tried changing how the device starts, by copying the ROM into RAM instead of paging it, and now it works. This isn't how the hardware works so I still need to find out why it failed before and fix it, but I now know where to look. Thanks for the help, but no need to continue comparing traces. Tha...
by hoglet
Mon Nov 13, 2017 6:08 pm
Forum: emulators
Topic: MAME: Tube devices
Replies: 68
Views: 3010

Re: MAME: Tube devices

Thanks, I'll work with that trace for now.

It looks like it is actually from v100, as the reset vector jumps to 0x3001730

But that's fine, as we have a disassembly for this version.

Dave
by hoglet
Mon Nov 13, 2017 4:34 pm
Forum: emulators
Topic: MAME: Tube devices
Replies: 68
Views: 3010

Re: MAME: Tube devices

Ah, it's this one: https://github.com/hoglet67/b-em/blob/master/roms/tube/ARMeval_100.rom Brazil version -.005 (8th August 1986) I'm now slightly confused as to what this is exactly.... But it does seem to work OK in PiTubeDirect. To make comparing traces easier, is there any chance you could make a...
by hoglet
Mon Nov 13, 2017 4:25 pm
Forum: emulators
Topic: MAME: Tube devices
Replies: 68
Views: 3010

Re: MAME: Tube devices

Just noticed something a little strange.... Your Client ROM trace doesn't seem to match the disassembly on JGH's site for v1.00: http://mdfs.net/Software/Tube/ARM/v100.zip And the SHA-1 sum is different: dmb@greenhog:~$ wget http://mdfs.net/Software/Tube/ARM/Eval100.rom dmb@greenhog:~$ sha1sum Eval1...
by hoglet
Mon Nov 13, 2017 1:15 pm
Forum: emulators
Topic: MAME: Tube devices
Replies: 68
Views: 3010

Re: MAME: Tube devices

Hmm, can't see anything obvious.

Do you get the same results with the v1.01 client ROM?

It might be worth trying to generate an address trace from the Co Processor, and we could compare that with a similar trace from PiTubeDirect.

Dave

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